If you want some intermediate languages the following are possibles
Java Virtual Machine Code (the language Java compiles to) MicroSoft
Intermediate Language There are very clear definitions of both
available either on the Web or through a book. These would have the
advantage of you not having to write an interpreter and also provide
you with a large library. They are both available for Windows or Linux

Another alternative is PCode, again information for this is available
on the Web. PCode is a lot simpler than the above two.